目录
1.面向对象
核心：'对象'二字
一：先定义类
类是对象相似数据与功能的集合体
所以类体中最常见的是变量与函数的定义，但是类体其实是可以包含任意其他代码的
注意：类体代码是在类定义阶段就会立即执行，会产生类的名称空间
class Student:
# 1、变量的定义
stu_school = 'oldboy'
# 2、功能的定义
def tell_stu_info(stu_obj):
print('学生信息：名字：%s 年龄：%s 性别：%s' % (
stu_obj['stu_name'],
stu_obj['stu_age'],
stu_obj['stu_gender']
))
def set_info(stu_obj, x, y, z):
stu_obj['stu_name'] = x
stu_obj['stu_age'] = y
stu_obj['stu_gender'] = z
print(Student.__dict__)
属性访问的语法
1、访问数据属性
print(Student.stu_school) # Student.__dict__['stu_school']
2、访问函数属性
print(Student.set_info) # Student.__dict__['set_info']
Student.x=1111 #Student.__dict__['x]=111
print(Student.__dict__)
二：再调用类产生对象
stu1_obj = Student()
stu2_obj = Student()
stu3_obj = Student()
2.为对象定制自己独有的属性
问题1：代码重复
问题2：属性的查找顺序
stu1_obj.stu_name = 'egon' # stu1_obj.__dict__['stu_name']='egon'
stu1_obj.stu_age = 18 # stu1_obj.__dict__['stu_age']=18
stu1_obj.stu_gender = 'male' # stu1_obj.__dict__['stu_gender']='male'
print(stu1_obj.__dict__)
stu2_obj.stu_name = 'lili'
stu2_obj.stu_age = 19
stu2_obj.stu_gender = 'female'
print(stu2_obj.__dict__)
stu3_obj.stu_name = 'jack'
stu3_obj.stu_age = 20
stu3_obj.stu_gender = 'male'
print(stu2_obj.__dict__)
解决问题一：
解决方案一：
def init(obj,x,y,z):
obj.stu_name=x
obj.stu_age=y
obj.stu_gender=z
init(stu1_obj,'egon',18,'male')
init(stu2_obj,'lili',19,'female')
init(stu2_obj,'jack',20,'male')
解决方案二：
一：先定义类
class Student:
# 1、变量的定义
stu_school = 'oldboy'
# 空对象,'egon',18,'male'
def __init__(obj, x, y, z):
obj.stu_name = x # 空对象.stu_name='egon'
obj.stu_age = y # 空对象.stu_age=18
obj.stu_gender = z # 空对象.stu_gender='male'
# return None
# 2、功能的定义
def tell_stu_info(stu_obj):
print('学生信息：名字：%s 年龄：%s 性别：%s' % (
stu_obj['stu_name'],
stu_obj['stu_age'],
stu_obj['stu_gender']
))
def set_info(stu_obj, x, y, z):
stu_obj['stu_name'] = x
stu_obj['stu_age'] = y
stu_obj['stu_gender'] = z
# print('========>')
二：再调用类产生对象
调用类的过程又称之为实例化，发生了三件事
1、先产生一个空对象
2、python会自动调用类中的__init__方法，然后将空对象已经调用类时括号内传入的参数一同传给__init__方法
3、返回初始完的对象
stu1_obj = Student('egon', 18, 'male') # Student.__init__(空对象,'egon',18,'male')
stu2_obj=Student('lili',19,'female')
stu3_obj=Student('jack',20,'male')
总结 __init__ 方法
1.会在调用类时自动触发执行，用来为对象初始化自己独有的数据
2.__init__内应该存放是为对象初始化属性的功能，但也可以存放任何其他代码
类调用时就立刻执行的代码都可以放再该方法内
3.__init__必须返回None(默认回返None)
3.属性查找
class Student:
# 1、变量的定义
stu_school='oldboy'
count=0
# 空对象,'egon',18,'male'
def __init__(self,x,y,z):
Student.count += 1
self.stu_name=x # 空对象.stu_name='egon'
self.stu_age=y # 空对象.stu_age=18
self.stu_gender=z # 空对象.stu_gender='male'
# return None
# 2、功能的定义
def tell_stu_info(self):
print('学生信息：名字：%s 年龄：%s 性别：%s' %(
self.stu_name,
self.stu_age,
self.stu_gender
))
def set_info(self,x,y,z):
self.stu_name=x
self.stu_age=y
self.stu_gender=z
def choose(self,x):
print('正在选课')
self.course=x
stu1_obj=Student('egon',18,'male') # Student.__init__(空对象,'egon',18,'male')
stu2_obj=Student('lili',19,'female')
stu3_obj=Student('jack',20,'male')
print(stu1_obj.count)
print(stu2_obj.count)
print(stu3_obj.count)
类中存放的是对象共有的数据与功能
一：类可以访问：
1、类的数据属性
print(Student.stu_school)
2、类的函数属性
print(Student.tell_stu_info)
print(Student.set_info)
二：但其实类中的东西是给对象用的
1、类的数据属性是共享给所有对象用的，大家访问的地址都一样
print(id(Student.stu_school))
print(id(stu1_obj.stu_school))
print(id(stu2_obj.stu_school))
print(id(stu3_obj.stu_school))
Student.stu_school='OLDBOY'
stu1_obj.stu_school='OLDBOY'
print(stu1_obj.stu_school)
print(Student.stu_school)
print(stu2_obj.stu_school)
print(stu3_obj.stu_school)
2、类中定义的函数主要是给对象使用的，而且是绑定给对象的，虽然所有对象指向的都是相同的功能，但是绑定到不同的对象就是不同的绑定方法，内存地址各不相同
类调用自己的函数属性必须严格按照函数的用法来
print(Student.tell_stu_info)
print(Student.set_info)
Student.tell_stu_info(stu1_obj)
Student.tell_stu_info(stu2_obj)
Student.tell_stu_info(stu3_obj)
Student.set_info(stu1_obj,'EGON',19,'MALE')
Student.tell_stu_info(stu1_obj)
绑定方法的特殊之处在于：谁来调用绑定方法就会将谁当做第一个参数自动传入
print(Student.tell_stu_info)
print(stu1_obj.tell_stu_info)
print(stu2_obj.tell_stu_info)
print(stu3_obj.tell_stu_info)
stu1_obj.tell_stu_info() #tell_stu_info(stu1_obj)
stu2_obj.tell_stu_info() #tell_stu_info(stu2_obj)
stu3_obj.tell_stu_info() #tell_stu_info(stu3_obj)
stu1_obj.choose('python全栈开发')
print(stu1_obj.course)
stu2_obj.choose('linux运维')
print(stu2_obj.course)
stu3_obj.choose('高级架构师')
print(stu3_obj.course)
l1=['aa','bb','cc'] # l=list([1,2,3])
l2=[111,222,333] # l=list([1,2,3])
print(l1.append)
print(list.append)
l1.append('dd')
l2.append('dd')
print(l1)
print(l2)
list.append(l1,'dd')
list.append(l2,'dd')
print(l1)
print(l2)
homework
# 选课系统项目中涉及到诸多数据与功能，要求引入面向对象的思想对其进行高度整合
# 1、学校数据与功能整合
# 2、课程数据与功能进行整合
# 3、学生数据与功能进行整合
# 4、讲师数据与功能进行整合
# 5、班级数据与功能进行整合
# 思路：
# a.学生相关的数据和学生相关功能整合成对象
# b.从学生中相似的数据提取出类
# 方式一
class School:
school_name='oldboy'
def __init__(self,nickname,address):
self.nickname=nickname
self.address=address
self.classes=[]
def related_class(self,class_obj):
self.classes.append(class_obj)
def tell_classes(self):
print(self.nickname,self.address)
for class_obj in self.classes:
class_obj.tell_course()
class Class:
def __init__(self,name):
self.class_name=name
self.course=None
def relate_course(self,course_obj):
self.course=course_obj
def tell_course(self):
print('%s '%(self.class_name),end='')
self.course.tell_course()
school_obj1=School('老男孩魔都校区','上海')
school_obj2=School('老男孩帝都校区','北京')
class Course:
def __init__(self,name,period,price):
self.course_name=name
self.course_period = period
self.course_price = price
def tell_course(self):
print('<课程信息:课程名字：%s，课程周期：%s，课程价格：%s>'
%(self.course_name,self.course_period,self.course_price)
)
course_obj1=Course('python全栈开发','六个月','20000')
course_obj2=Course('linux运维','五个月','18000')
class_obj1=Class('脱产14班')
class_obj2=Class('脱产15班')
class_obj3=Class('脱产29班')
class_obj1.relate_course(course_obj1)
class_obj2.relate_course(course_obj2)
school_obj1.related_class(class_obj1)
school_obj1.related_class(class_obj2)
school_obj2.related_class(class_obj3)
school_obj1.tell_classes()
class Student:
pass
# 方式二
class School:
# 校区的名字：如"老男孩上海校区"
# 校区的地址：如"上海虹桥"
def __init__(self, name, address):
self.name = name
self.address = address
self.classes_list = []
def create_classes(self, class_name):
self.classes_list.append(class_name)
class_obj = Class(class_name, self.name)
return class_obj
class Class:
# 班级名字
# 班级所在校区
def __init__(self, name, school_name):
self.name = name
self.school_name = school_name
self.courses_list = []
def create_course(self, course_name, course_period, course_price):
self.courses_list.append(course_name)
course_obj = Course(course_name, course_period, course_price)
return course_obj
class Course:
def __init__(self, name, period, price):
self.name = name
self.period = period
self.price = price
class Student:
# 学生的学校
# 学生的姓名
# 学生的年龄
# 学号
# 学生的性别
def __init__(self, school_name, name, age, number, gender):
self.school_name = school_name
self.name = name
self.age = age
self.number = number
self.gender = gender
self.student_course_list = []
self.score_dic = {}
def choose_class(self, course_name):
self.student_course_list.append(course_name)
self.score_dic[course_name] = 0
class Teacher:
# 老师的名字
# 老师的年龄
# 老师的薪资
# 老师的等级
def __init__(self, name, age, salary, level):
self.name = name
self.age = age
self.salary = salary
self.level = level
# 老师创建完毕后，可以为学生打分
def change_socre(self, student_obj, course_name, sorce):
student_obj.score_dic[course_name] = sorce
school_obj1 = School('老男孩上海校区', '上海虹桥')
print(school_obj1.__dict__)
class_obj1 = school_obj1.create_classes('上海14班')
print(class_obj1.__dict__)
course_obj1 = class_obj1.create_course('python全栈', '六个月', 19800)
print(course_obj1.__dict__)
student_obj1 = Student(school_obj1.name, 'roger', 18, '007', 'male')
student_obj1.choose_class(course_obj1.name)
print(student_obj1.__dict__)
teacher_obj1 = Teacher('tank', 28, 100000, 10)
print(teacher_obj1.__dict__)
teacher_obj1.change_socre(student_obj1, course_obj1.name, 90)
print(student_obj1.__dict__)
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